User Sanchayan Dutta

41 votes

3 answers

9k views

How does a quantum computer do basic math at the hardware level?

asked Mar 24, 2018 at 5:37

35 votes

5 answers

4k views

Introductory material for quantum machine learning

asked May 26, 2018 at 23:24

34 votes

1 answer

13k views

How are quantum gates implemented in reality?

asked Mar 23, 2018 at 11:12

25 votes

3 answers

3k views

Why do optical quantum computers not have to be kept near absolute zero while superconducting quantum computers do?

asked Mar 14, 2018 at 21:54

25 votes

3 answers

5k views

What exactly are anyons and how are they relevant to topological quantum computing?

asked May 11, 2018 at 15:17

24 votes

2 answers

6k views

Why does the "Phase Kickback" mechanism work in the Quantum phase estimation algorithm?

asked Jul 1, 2018 at 19:47

21 votes

1 answer

2k views

What is the use of categorical quantum mechanics?

asked May 3, 2018 at 9:10

21 votes

2 answers

20k views

Density matrices for pure states and mixed states

asked Jun 14, 2018 at 18:55

19 votes

2 answers

2k views

What is the mathematical justification for the "universality" of the universal set of quantum gates (CNOT, H, Z, X and π/8)?

asked Mar 23, 2018 at 19:56

18 votes

1 answer

3k views

If quantum gates are reversible how can they possibly perform irreversible classical AND and OR operations?

asked Mar 15, 2018 at 10:58

18 votes

3 answers

747 views

What exactly is meant by "noise" in the following context?

asked Mar 13, 2018 at 10:05

15 votes

6 answers

8k views

Is there any online Bloch sphere simulator?

asked May 20, 2019 at 13:21

13 votes

2 answers

2k views

Quantum algorithm for linear systems of equations (HHL09): Step 1 - Confusion regarding the usage of phase estimation algorithm

asked Jun 19, 2018 at 8:00

12 votes

1 answer

1k views

How does Fourier sampling actually work (and solve the parity problem)?

asked Mar 17, 2018 at 6:30

12 votes

1 answer

848 views

Embedding classical information into norm of a quantum state

asked May 27, 2018 at 14:57

12 votes

4 answers

4k views

How to quickly calculate the custom U3 gate parameters $\theta, \phi$ and $\lambda$ for any unitary?

asked May 26, 2019 at 2:35

12 votes

2 answers

1k views

Understanding Google's “Quantum supremacy using a programmable superconducting processor” (Part 1): choice of gate set

asked Sep 28, 2019 at 14:23

11 votes

1 answer

1k views

How is Grover's algorithm used to estimate the mean and median of a set of numbers?

asked May 1, 2018 at 12:34

10 votes

2 answers

962 views

Quantum algorithm for linear systems of equations (HHL09): Step 2 - What is $|\Psi_0\rangle$?

asked Jun 19, 2018 at 11:03

10 votes

2 answers

2k views

Quantum algorithm for linear systems of equations (HHL09): Step 2 - Preparation of the initial states $|\Psi_0\rangle$ and $|b\rangle$

asked Jun 24, 2018 at 7:08

10 votes

3 answers

4k views

What precisely is the quantum extended Church-Turing thesis?

asked May 7, 2019 at 15:42

9 votes

1 answer

687 views

What is recursive Fourier sampling and how does it prove separations between BQP and NP in the black-box model?

asked Jan 14, 2019 at 21:41

9 votes

1 answer

578 views

Is it possible to speed up the generation of the weighting matrix using a quantum algorithm?

asked Jun 18, 2018 at 6:17

9 votes

1 answer

1k views

Understanding Google's “Quantum supremacy using a programmable superconducting processor” (Part 2): simplifiable and intractable tilings

asked Sep 28, 2019 at 16:55

9 votes

1 answer

759 views

Why does representation theory often arise in the context of quantum algorithms for the hidden subgroup problem?

asked Nov 23, 2019 at 18:36

8 votes

1 answer

2k views

How exactly does Simon's algorithm solve the Simon's problem?

asked Apr 15, 2018 at 6:45

8 votes

1 answer

834 views

Quantum algorithm for linear systems of equations (HHL09): Step 1 - Number of qubits needed

asked Jun 19, 2018 at 8:40

8 votes

2 answers

2k views

What are theta, phi and lambda in cu1(theta, ctl, tgt) and cu3(theta, phi, lam, ctl, tgt)? What are the rotation matrices being used?

asked Jul 11, 2018 at 11:04

8 votes

1 answer

636 views

SWAP gate(s) in the $R(\lambda^{-1})$ step of the HHL circuit for $4\times 4$ systems

asked Jul 12, 2018 at 21:32

8 votes

2 answers

384 views

Resources for Quantum Communication Complexity

asked Jul 29, 2018 at 8:21

Stack Exchange Network

87 Questions

How does a quantum computer do basic math at the hardware level?

Introductory material for quantum machine learning

How are quantum gates implemented in reality?

Why do optical quantum computers not have to be kept near absolute zero while superconducting quantum computers do?

What exactly are anyons and how are they relevant to topological quantum computing?

Why does the "Phase Kickback" mechanism work in the Quantum phase estimation algorithm?

What is the use of categorical quantum mechanics?

Density matrices for pure states and mixed states

What is the mathematical justification for the "universality" of the universal set of quantum gates (CNOT, H, Z, X and π/8)?

If quantum gates are reversible how can they possibly perform irreversible classical AND and OR operations?

What exactly is meant by "noise" in the following context?

Is there any online Bloch sphere simulator?

Quantum algorithm for linear systems of equations (HHL09): Step 1 - Confusion regarding the usage of phase estimation algorithm

How does Fourier sampling actually work (and solve the parity problem)?

Embedding classical information into norm of a quantum state

How to quickly calculate the custom U3 gate parameters $\theta, \phi$ and $\lambda$ for any unitary?

Understanding Google's “Quantum supremacy using a programmable superconducting processor” (Part 1): choice of gate set

How is Grover's algorithm used to estimate the mean and median of a set of numbers?

Quantum algorithm for linear systems of equations (HHL09): Step 2 - What is $|\Psi_0\rangle$?

Quantum algorithm for linear systems of equations (HHL09): Step 2 - Preparation of the initial states $|\Psi_0\rangle$ and $|b\rangle$

What precisely is the quantum extended Church-Turing thesis?

What is recursive Fourier sampling and how does it prove separations between BQP and NP in the black-box model?

Is it possible to speed up the generation of the weighting matrix using a quantum algorithm?

Understanding Google's “Quantum supremacy using a programmable superconducting processor” (Part 2): simplifiable and intractable tilings

Why does representation theory often arise in the context of quantum algorithms for the hidden subgroup problem?

How exactly does Simon's algorithm solve the Simon's problem?

Quantum algorithm for linear systems of equations (HHL09): Step 1 - Number of qubits needed

What are theta, phi and lambda in cu1(theta, ctl, tgt) and cu3(theta, phi, lam, ctl, tgt)? What are the rotation matrices being used?

SWAP gate(s) in the $R(\lambda^{-1})$ step of the HHL circuit for $4\times 4$ systems

Resources for Quantum Communication Complexity